Tajikistan suffered five years of civil war after the collapse of the Soviet Union, followed by widespread drought and famine, and the landlocked nation in Central Asia has struggled to rebuild its economy and infrastructure. Almost all the country is in the Pamir Mountains, with a few lower-lying areas in river valleys. The highest mountain, once known as Communism Peak, is now Ismoil Somoni Peak, after the Father of the Tajik nation. Hillwalking and mountain climbing in the spectacular scenery is probably the best hope for a regeneration of the tourist industry. Exports are aluminium and cotton, though both have contributed to pollution problems: The aluminium plant generates waste gases that have been blamed for birth defects, While toxic runoff from cotton irrigation has contributed to the problems of the Aral Sea. The capital is Dushanbe which has a number of Soviet era public buildings. North of Dushanbe is the five kilometre Aznab Tunnel, which when fully paved and ventilated, will improve access to the northern region, and will eventually be a part of the planned New Silk Road from Iran to China. A new bridge over the River Panj, built with American help, will improve communications with Afghanistan.